Excavating machine



Bday 15,1923.

J. A. MaCKlLLlCAN ET AL.

EXCAVATING MACHINE 1921 5 Sheets-Sheet 1 www Filed. March 16.

lllllll! May l5, 1923. 1,455,541

J. A. MafG'KlLLlcAN ET Al.

EXCAVATING MACHINE Filed March 1e. 1921 5 sheets-sheet 2v w L\ (\7 N Q :i n D [Elfe/2351:;

May 15, 1923.

J. A. MaCKH-LICAN ET AL EXCAVATING MACHINE Filed March 16. 1921 5 Sheets-Sheetl 5 5f m @JW j@ May 15, 1923.

J. A. MaCKlLLlCAN ET AL EXCAVATING MACHINE Filed March 16. 1921 '5 Sheets-Sheet 5 Patented May 15, 1923.r

UNITED STATES v`PATENT oFFlcI-z.

JAMES A. MAOKILLICAN AND FRANK L. LIPCSEY, DF HIBBING, IJINNISOTA.'

EXCAVATING MACHINE. A

appueauqn med umn 1e, 1921. serial 11. 452,375.

To all wlwm it may concern;

Be it known that we, JAMES A. MACKTL- LIcAN, and FRANK LPLIPCSEY, both residing at Hibbin in the county of St. Louis and State of innesota, have invented new -and useful Improvements in Excavating Machines, of `which the following is a specification.

. This invention relates to an excavating and loading machine of the so-called shovel or scoop type and built relatively low so that it may be used underground in tunnels and mines',.subways, drifts, rand the like.

One object of the invention is to so arrange the parts of the machine that the center of gravity is between the wheels of the truck on which the parts are mounted or to the rear of the fulcrum point of the shovel lifting arms and thusv reduce the over-all length of the machine andv the amount of counter-weight required to balance the machine as the shovel or scoop is raised into and' out of loading position above the truck.

Another object of the invention is to provide mechanism for imparting a steady straightforward thrust to the scoop or shovel and to do this with the minimum amount of power by having an indirect connection .between the motor and scoop through a geary train.

A further object of the invention is to arrange the parts so that the turn-table on which the shovel or scoop is mounted may be swung around to either side of the truck or car a sufficient distance to reach working places at the sides of the car and thus facilitate excavating in corners and along the sides of La drift, and furthermore to enable the machine to work around a curve.

The invention consists further in the matters-hereinafter described 'and more particularly pointed out in the appended claims.

In the accompanying drawings- Fig. 1 is a vertical longitudinal sectional View of an excavating and loading machine constructed in accordance with 'our invention;

Fig. 2 is a horizontal sectional view taken on line 2-2 of Fig. 1;

Fig. 3 is a top plan view of .one of the gear shifting frames,'to be hereinafter described; v

Fig. 4 is a sectional view taken on line 4-4 of Fig. 3;

. Fig-5 is a rear view of the machine;

Fig. 6 is a vertical sectional view taken on line 6-6 of Fig. 1;

F1g. 7 is an elevational view of one of the shovel or scoop arms, viewing the same from the inside thereof;

Flg. 8 1s a side view ofthe machine showing the scoop'cr shovel arms raised into dumping osition;

F1g. 9 1s a perspective view showing the manner in which the gear shifting mechanism is actuated;

Fig. 10 is a top plan view of the truck frame, showing t e pivoted bolster in the position occupied when the shovel or scoop is directly in front of the machine and in its starting position; l

Fig. 11v is a like vlew of the truck frame, showing the bolster swung into a position occupied when the shovel or scoop is at one side of the machine;

Fig. 12 is a plan view of that part of they truck frame provided with the grooved track for the rollers on the bolster;

Fig. 13 is a plan view of the rack associated with the truck frame;

Fig. 14 is a perspective view of the bol-l ster; and

Fig. 15 `is a vertical sectional view taken on line 15-15 of Fig. 10.

The machine shown in the drawings comprises a truck or carriage 1 having wheels 2 to run on rails 3. Above the truck` 1 is a horizontal deck 4 having pivotal connection with the truck 1 in the manner to be hereinafter described. 'Secured te thedeck 4 are two upright standards 5, 5 arranged on opposite sides lofthe deck. Extending between and journaled in said standards are two horizontally arranged shafts 6, 7, as shown in Fig. 1.

Oneach side of the deck 4 is a shovel or scoop arm 8 having its inner end curved upward, as shown in Fig. 7 and journaled on the shaft 6. When the arms 8 are in lowered position they extend horizontally forward from the deck 4, as shown in Figs. 1 and 2. Between the' arms is a shovel or scoop 9. This is supported by the arms by being secured to roller carriages 10, one on each side thereof and mounted to roll endwise in elongated slots or trackways 11 in the arms. To move the shovel or scoop 9 endwise ofthe arms, both forward and backward, we provide for each arm a-cable 12, which is preferably located inside of the arm, as shown in the drawmgs. Each cable 12 is trained over a plurallty of grooved sheaves 13 carried by the assoclated arm and also about a grooved pulley or sheave '14 at the inner end of the arm and fixed on the shaft 6. Securedto each side of the shovel or scoop 9 below the roller carriage 10 is a bar 15, to the opposite ends of which are connected the ends of the associated cable 12, so that when the shaft 6 is rotated in one direction, the shovel or scoop 9 will be moved toward the outer ends of the arms 8, and when rotated in the opposite direction it will be moved toward the inner ends thereof.

For raising the shovel or scoop 9 into dumping position above the 1, as shown in Fig. 8, we provide two segmental racks 16, 16, both on the shaft 7. The racks have a1 :uate slots 16a for the shaft 6 to extend therethrough and not interfere with the turning of the racks. These racks are arranged adjacent the standards 5, inside thereof, and there is one for each arm 8. Each rack has an outwardly projecting portion 17 connected with the associated arm 8 by a link 18, as shown in Figs. l and 8. rThe links are connected together above the arms by a yoke- 18a. As clearly shown in Fig. 1, the point of connection between each arm 8 and its link 18 is between the ends of the arm or forward of the pivotal or fulcrum point 6, so that power is applied between the ends of the arms when raising the same.

Fixed on the shaft 6 is a worm gear 19 in mesh with a worm 20 on an inclined shaft 21 journaled in a bracket 22 on a horizontal cross-bar 23 supported above the deck 4, as shown in Fig. 1. The lower end of the inclined shaft 21 extends into an open frame 24 through an elongated slot 25, as shown in Figs. 3 and 4. This permits the frame 24 to lbe moved transverse of the shaft 21, and for this purpose said frame is slidably mounted on a cross-bar 26 supported above the deck 4 below the rod 23, as shown in Fig. 1. Fixed on the inner end of the shaft 21, in the frame 24, is a gear wheel 27, and on opposite side-s thereof are gear pinions 28, 28a. These are fixed on shafts journaled in the frame, and suc-h shafts have friction discs 29, 29a. These discs are on opposite sides of a main friction disc.30 fixed on the main driven shaft of an electric motor 31 or other prime mover mounted on the deck 4.

scoop a straightforward thrust into the material to be excavated, the frame 24 is shifted to move the gear pinion 28 into mesh with the gear wheel 27, and this of course moves the fric-tion disc 29 into frictional engagement with the main disc 30. As a result, the worm gear 19 is rotated in the direction required to exert a pull. on the cable 12 to move the shovel or scoop in a forward direction. To reverse the movement of the scoop, that is, to return it tov its position back toward the inner ends of the arms, the frame 24 is shifted in the other direction to bring the gear pinion 28a into mesh with the gear wheel 27 and the ,friction disc 29a into engagement with the main disc 30.

In Fig. 9, we have shown one way in which this frame 24 may be shifted manually. At one side of the deck 4 is a hand lever 32 pivoted on a bracket 33 secured to the deck. A link 34 connects the lower end of the lever 32 with the frame 24, and by moving the lever back and forth it is obvious that the frame 24 will be shifted endwise. To hold the lever 32 in any one of three predetermined positions, there is a notched segment plate 35 secured to the bracket 33.

Extending across the deck 4 and j ournaled thereon is a shaft 36, as shown in Figs. 1, 2 and 5. This shaft is to the rear of the segmental racks 16, and fixed on the shaft are two gear wheels 37, 37, one in mesh with each of the segmental racks 16. Fixed on the shaft 36 is a worm gear 38 in mesh with a worm 39 on an inclined shaft 4 0 having its upper end extending into a shift frame 41. The upper end of the shaft 40 is'provided with a gear wheel 42'arranged between gear pinions on shafts journaled in the frame 41 and having at their outer ends friction discs 43, 43al on opposite sides of the main driving disc 30, as shown in Fig. 2. This frame 41 is shifted in the same manner as the one previously described by a hand lever 44 connected with the frame byv a link 45. When the frame 41 has been shifted to bring the friction disc 43 into engagement with the main disc 30, power is then transmitted to the shaft 40 from the motor 31, and throu h the gear train described, the segmental rac s 16 are turned in a direction to raise the arms 8 up above the machine into dumping position. When the frame 41 is,shifted in the opposite direction so as to bring the disc 43a into engagement with the main disc 30, the operation is reversed andthe arms 8 are brought down into position extending forward in front of the machine, as shown in Fig. 1.

The deck 4 is pivotally connected with the truck or carriage 1 in the following manner, so that the deck may be turned ina horizontal plane to either side of the t'ruck 1 in order that the shovel or scoop 9 may reach working places at the sides of the machine.

The truck or carrie e 1 has an open frame 46 made preferably o structural steel, channel shape, as shown in the drawings. Within this frame 46 is arran ed a casting 47 havin the general shape s own in Figs. 10, 11 an 12. This casting has a rear crossniember 48, which extends across the frame 46, and said member 48 has two forwardly projecting ears or lugs 49, 49a spaced apart and being adjacent the ends of the crossmember 48, as shown in said figures. tegral with and extending forward from the cross-member 48 is the curved part 50 of the castino 47, and this part is provided with an inwardly opening groove 51 being continuous from one end of the member 50 to the other and following the gene'ral curvature thereof. Located in the opening within the member 47 is a bolster 52 havingat its ends outwardly extending pins 53, on which are journaled rollers 54, which travel in the curved trackway 51. At one end, the bolster 52 has an inwardly extending portion 55 spaced vertically below the body vpart of the bolster and connected by a pivot pin 56 l with a link 57, which in turn 1s connected by a pivot pin 58 with the forwardly projecting lug 49 of the cross-member 48. Above the link 57 is a link 59 connected by a pivot member 60 with the bolster 52 ad` jacent its end opposite the end with which the link 57 is connected. The other end of the link 59 is connected by a pivot member 6l with the other forwardly projecting lug 49a of the cross-member 48. The deck 4 is made open .and of structural steel elementsincluding longitudinal -beams 62 supported above the bolster 52 by brackets 63, as shown in Fig. 15.

Arranged on the truck 0r car 1 to the rear of the bolster 52 is a rack 64 having the curvature shown in the drawings and more particularly in Figs. 10, 11 and 12. This rack 64 has a rearwardly extending stifening ange 65, which also serves as a guide rail for a grooved roller 66 journaled in a bracket 67 secured to the deck 4y at the rear thereof, as shown in Figs. 1, 5 and 8. Opposite the bracket 67 on 'the inside of the deck and secured thereto is a bracket 68, in which in Fig.`v 2. At the upper end ofthe shaft 73 is fixed a gear wheel 74 located between the gearpinions 75, 7 5", which are mounted on shafts journaled in a shift frame 76 similar to the shift frames' 24 and 41'heretofore described. The shafts on whichA the gear pinions 75, 75a are mounted are also provided with friction discs 77, 77 arranged at opposite sides of a main driving disc 78 of the electric moto'r 31. The frame 76 is shifted to move the gear pinions 7 5, 7 5a al1 ternately into and out of mesh with the gear wheel 74 by means of a ivoted hand lever 79y connected with the shlft frame by a link 80 in the same manner as shown in Fig. 9.

The machine shown and described operates as follows. When operating against a bank or pile of material to be excavated directly in front of the machine, the latter is run up into a position in front of such material with the arms 8, 8 lowered so as to extend horizonally straight infront of the machine and the shovel or scoop 9 in its starting position back in front of the truck 1, as shown in Fig. 1. At this time all of the hand levers 32, 44, and 79 are in the middle notch in their respective segment plates 35, and the gear train is in neutral position so that no power is transmitted to the operative parts of the machine by the motor. V

To fill the shovel or scoop 9 with a load,

' the lever 32 is pulled Outward from the machine to move the disc 29 into frictional en gagement with the driving disc 80. This will transmit power from the motor to the shaft 6 through the gear wheel `19 and draw on the cable 12 in a direction to move the scoop or shovel 9 outward and into the material` to be excavated, as indicated by dotted llines in Fig. 1. After the shovel has been given ,this straightforward thrust into the material and has thus picked up a load, the operator moves the lever 32 back to neutral position to cut off the power to the shovel.

The next operation is for the operator to move the lever 44 from its neutral position outward away from the truck 1 and thereby shift the friction disc 43 into engagament with the main disc 30 and the associated gear pinion into mesh with the gear wheel 42. When this has been done, the motor will turn the segmental racks 16 to raise the arms 8 and carry the shovel or scoop, while at the outer ends of the arms, into position .above the machine and directed backward to discharge or dump the load out of the shovel into a hopper or ona conveyer belt provided for carrying away the material as fast yas it is excavated. When the shovel has reached this position, the operator moves the lever 44 back into neutral position to disconnect said gear train from the motor.

To return the shovel to its starting position, the operator, after the shovel has dumped itself, moves the lever 44 from neutral position inward toward the truck 1 to shift the other friction disc 43a into engagement with the main disc 30 and thus connect the motor with the gear train including the segmental racks 16 and turns them in a direction to lower the arms 8 and carry the 4shovel downward into horizontal position starting position, as shown in Fig. 1.

Should 4it be desired to excavate from working places or corners'on either side of the machine, the deck 4 is turned about the pivotal connection between the links, as heretofore described, to move the shovel over toward whichever side of the machine the work is to be done. To move to the right-handV side ofthe machine, the lever 79 is moved from" its neutral position in toward the truck l to bring the friction disc 77i into engagement with the driving disc 78 and thus, through the gear train including the worm wheel 71, the pinion travels along the stationary rack 64 in a direction to swing the deck toward the right of the machine about the pivotal point 56, due to the arrangement of the bolster 52 and links 57 and 59, as heretofore described. In Fig. 11, we have shown by dotted lines the deck 4 of the machine swung to a position with the shovel operating onvthe righthand side of the machine, and in dotted lines, the bolster 52 in the position occupied at that time. After the shovel has reached the position required at the right-hand side of the machine, the lever 79 is moved back into neutral position to cut out the motor from the gear train, and thus hold the shovel in the position into which it has been swung. While the shovel is in that position, it is given a straightforward thrust, raised to dump, and brought back 'into the starting position again, and those operations repeated as long as necessary by operating the levers 32 and 44, as heretofore described.-

To bring the shovel back into a position directlv in front of the machine from any one of its adjusted positions at the righthand side of the machine, the lever 79 is moved from neutral position outward from the truck 1 to move the friction disc 77 into engagement with they driving disc 78, and by the gear train described the pinion70 will travel along the rack 64 back to the position shown in Figs. 1 and 10, whereupon the lever 79 is moved into neutral position to disconnect the motor from that gear train.

Should it be desired to excavate 'on the left-hand' side of the machine, the lever 79 Maasai is moved from neutral position out from the truck 1 as just described, and by the gear train mentioned,4 the pinion 70 will travel along the other side of the rack 64,.and the deck, by reason of its connection with the bolster 52, will then swing 0r pivot about the other pivotal point 58. After the deck has been swung to the point desired or permitted by the structure, the lever 79 is thrown back into neutral position to disconnect the motor from that gear train.

The machine described and shown, by reason of the arrangement and construction of the several parts, is made relatively low so that it can be used effectively in low working sol places, such as in tunnels, mines, subways, or

the like. The machine is simple in its construction and operation and therefore may be handled without great expense because unskilled labor can be used to operate it. Then again, all of the operating parts are fairly well exposed to view and accessible, thereby permitting ready lubrication and repair to be made when needed. The fact that the various operations of the machine are independent of each other and under the control of the operator, the shovel or scoop may be moved back and forth into and out of the material to bey excavated several times, in order to pick up a full load, before being raised into dumping position.

Another advantage of this construction resides in the fact that the fulcrum point of the lifting mechanism is positioned between the wheels 2, 2 on which the machine is mounted, and therefore avoids the use of an ext-ra weight lto counterbalance the machine as the shovel is being raised with al load. This thereby reduces the amount of material required to be placed in the machine when being built, and furthermore reduces the expense of building, as well as reduces the weight of the machine to a minimum so that a great deal of power is not required to move it over the rails. Furthermore, a relatively light clamp may be used to hold down the rear end of the machine.

Another advantage resides in the fact that the gear ratio may be made such as to reduce to the minimum the amount of power requiredI to move the several parts of the mechanism. Y

Another advantage arising out of the construction is that the shovel may be swung to -either side of the truck 1 and thereby be used to excavate from working places on opposite sides of the machine. This vis especially advantageous when cutting around curves, as when excavating from a drift into an enlarged compartment or chamber. The deck being swung on pivotal points adja cent the sides of the truck, instead of at the center, allows the scoop to reachV places farther from the sides ofthe truck than vcould be done with only one pivotal point and that in the center line of the truck.

Other and further advantages will be apparent to. those skilled in the art to which our invention relates and, while we have shown and described 1n detail herein an excavating machine embodying the features of our invention, yet it is to be of course understood that the various details of construction and arrangementof parts may be variously chan d and modified without departing from t e spirit and scope of our invention. l

We claim as our invention:

l. An excavating machine, comprising a truck, a deck above the same, power actuated excavating means carried by the deck, and means pvotally connecting the deck 'with the truck at two points, one adjacent each side of the truck so that the deck may be swung horizontally to carry the excavating means to either side of the truck on the pivotal point nearest the side of the truck beyond which the excavating means is swung.

2. An excavating machine, comprising a truck, a deck above the same, power actuated excavating means carried by the deck, a member fixed to the truck and 'having a curved track, a bolster connected with the deck and engaging said track, and means pvotally connecting said bolster with said member at two points, one adjacent each end of said bolster, so that the deck may be swung horizontally to carry the excavating means to either side of the truck on the pivotal point nearest the side of the truck loeyond which the excavating means is swung.

3. An excavating machine, comprising a truck, a deck above the same, power actuated excavatin means carried by the deck, a member xed to the truck and yhaving a curved track, a bolster connected with the deck and having rollers engagin said track, means pvotally connectin said olster with said member at two polnts, one adjacent each end of the bolster so that the deck may be swung horizontally on either pivotal point, an power actuated means for swinging said deck on said pivotal points.

4. An excavating machine, comprising a truck, a deck above the same, power actuated excavating means carried by the deck, ,a member fixed to the truck and having a curved track, a bolster connected with the deck and having rollers engagin said track, means pvotally connecting saidolster with said member at two points, one adjacent each end of the bolster so that the deck may be swung horizontally on either pivotal point, a curved rack fixed on the truck, and a gear wheel carried by the deck and in mesh with saidrack.

5. An excavatlng machine, comprising a truck, a deck above the same, power actuated member fixed tosaid truck and having a cross-bar at its inner end and a curved track in the forward part of the same, said crossbar having forwardly projecting lugs, at different levels and adjacent the ends of the same, a bolster above said lugs and connected with the deck and having rollers engagin' said track, and links pvotally connecte with said bolster and said lugs so that the deck may be swung horizontally on either of two pivotal points, one adjacent each end of said bolster.

6. An excavating machine, comprising a truck, a deck above the same, oweract'uated excavatingmeans carried by t e deck, a mem- ,ber ixed to said truck and having a crossbar at its inner end and a curved track in the forward art of the same2 said crossbar having orwardly projecting lugs, at diirent levels and adjacent the ends of the same, a bolster above said lugs and connected with the deck and having rollers engaging said track, and two links, one pivoted at one end to one lug and pvoted at the other end to the end of the bolster opposite said lug, the other link being pivoted at one end to the other lug and pivoted at the opposite end to the end of the bolster opposite the last mentioned lug.

7. An excavating machine, comprising a truck, a deck above the same, power actuated excavating means carried by the deck, a

member fixed to said truck and having a cross-bar at its inner end and a curved track in the forward part of the same, said crossbar having forwardly projecting lugs, at different levels and adjacent the ends of the same, a bolster above said lugs and connected with the deck and having rollers en ging said track, links pvotally connecte with said bolster and said lugs so that the deck may be swung horizontally on either of two pivotal points, one adjacent each end of said bolster, a curved rack xed on the truck in the rear of said cross-bar, and a gear wheel cariied by said deck and in mesh with said rac 8. An excavating machine, comprising a truck, a deck above the same, an arm pivoted at its inner end and carried by said deck, a scoop connected with said arm and adapted to be moved by the same into and out ofdumping position above said deck, power actuated means for raising and lowering said arm, and means pvotally connecting said deck with said truck at two points, one adjacent each side of the truck, so that the deck may be swung horizontally to carry the scoop to either side of the truck on the pivotal point nearest the side of the truck beyond which the scoop is swung.

j 9. An excavating machine, comprislng a truck, a deck above the same, an arm pivoted at its inner end and carried by said excavating means carried by the deck, a deck,'a scoop 'connected with said arm and 13 adapted to be moved by the same into and out of dumping position above said deck, power actuated means for raising and lowering said arm, a member xed to said truck and having a curved track, a bolster connected with said deck and havin rollers engaging said track,`means pivota ly connecting said bolster with said member at two points, one adjacent each end of said bolster so that the deck may be swun'g horizontally on either pivotal point, a curved rack fixed vto said truck in the rear of said track, and a gear wheel carried by said deck and in mesh with said rack.

10. An excavating machine comprising a deck, a pair of laterally spaced arms pivoted at their inner ends and carried by said deck, a scoop located between said arms and connected therewith in a manner permittin said scoop to be moved endwise thereo power actuated means for moving said scoop said arms and connected therewith in a.

manner permitting said scoop to be moved endwise thereof, sheaves fixed on said shaft,

one adjacent each arm, guide rollers on each arm, a cable for each arm and having its ends connected with said scoop and trained over said rollers and sheave of the associated arm, power actuated means for rotating said shaft and for raising and lowering said arms for moving the scoop into and out of dumpingI position above the deck, and manually operable means for controllin the application of power to said scoop an arms.

12. An excavating machine, comprising a deck, standards secured to said deck, two shafts extending between and supported by said standards, a pair of laterally spaced arms having their inner ends journaled on one of said shafts, a scoop between said -arms and connected therewith in a manner to be moved endwise thereof, segmental racks on the other of said shafts, one for each of saidv arms, eachv rack being connected with itsl associated arm intermediate the ends thereof, power actuated means for moving said scoop endwise of said arms and for turning said racks, and manually operable means for controlling the application of power to said scoop and said racks.

13. An excavating machine, comprising a deck, standards secured to said deck, two

tween the motor and said racks, said mechanisms including means whereby the motor may drive either one of said mechanisms' in either direction and independently of the other. v

14. An excavating machine, comprising a deck, standards secured to said deck, two shafts extending between and supported by said standards, a pair of laterally spaced arms having their inner ends journaled on one of said shafts, a scoop between said arms and connected therewith in a manner .t0 be moved endwise thereof, segmental racks on the other of' said shafts, one for each of said arms, each rack being connected with its associated arm intermediate the ends thereof, a gear wheel on the shaft on which said arms are mounted, a cable for each arm and havmg its ends connected with said scoop and actuated upon the turning of said gear wheel,` a counter-shaft to the rear of said racks, pinions on said counter-shaft and in mesh with said racks, a gear wheel on said counter-shaft, a motor, two-gear trains, one for each of said gear wheels and between the same and said motor, and means for shifting either of said gear trains in operative connection with said motor.

15. An excavating machine, comprising a therewith in a manner permitting the scoop to be moved endwise thereof, means for moving said scoop endwise of said arms, means for raising and lowering said arms for moving the scoop into and out of dumping position above the deck, means for pivotally connecting the deck with said truck so that the deck may be swung horizontally to carry the scoop' to opposite sides of the truck, a motor on said deck for operating all of said means, and means manually con- "trolled whereby the motorl may operate any of said means independently of the others.

16. The combination with a motor having a shaft with a friction disc thereon, of a gear shifting device, comprising a slidably mounted open frame having an elongated slot in one side thereof, a driven shaft extending into said frame through said slot ioo and having a gear Wheel xed thereto within said frame, gear pinions on the shaft journaled in said frame on opposite sides of said gear wheel and adapted to be moved with said frame into and out'l of mesh therewith, friction discs xed on the shaft carried by said frame and arranged onopposite sides of the friction disc on said motor Y shaft and moved into and out of contact with said last mentioned disc in the movement of said frame, and a manually operable lever conected with said frame for moving the same.

In testimony that we claim the foregoing as our invention, we aflixour signatures @his 10th day of March, A. D. 1921.

JAMES A. MAOKILLICAN. FRANK L. LIPCSEY. 

